This invention concerns an animal feed binder. More particularly, it is related to an improved binder composed of ozonated lignosulfonate.
As used herein, the term "lignosulfonate" refers to the reaction product of lignin which is inherently obtained during the sulfite pulping of wood, straw, corn stalks, bagasse and the like, and is a principal constituent of spent sulfite liquor which is derived from that process. The term also encompasses sulfonated lignin that is obtained by sulfonating lignin from pulping liquors of the kraft, soda and other well-known alkali pulping operations.
Animal feeds are generally produced with low cost by-product ingredients. These ingredients are often dusty, unpalatable, of low density, and have inadequate nutrient profile. To correct these shortcomings, ingredients are combined into a mixture with the necessary vitamins, minerals, and amino acids to provide adequate energy and protein, and to meet the nutrient requirements of the animals. This is normally accomplished by extrusion and/or compaction techniques to form pellets, blocks or briquettes. Extrusion and compaction eliminate ingredient segregation, increase bulk density, reduce dust, mask unpalatable ingredients, and reduce wastage. All of these benefits are dependent on the pellet, block or briquette maintaining its physical integrity.
Since feed formulations are typically dictated by the cost and availability of by-product ingredients, it is not always possible to produce durable pellets. Some ingredients such as animal fat, meat meal, ground corn, and oat hulls, have poor binding qualities and may even be antagonistic to binding. When such ingredients are used a binder, such as lignosulfonate, is often included to insure that a durable pellet is produced. Typically, lignosulfonate, a naturally occurring polymer generated in sulfite pulping of wood, is applied to the feed at a dosage of 25 to 50 lbs. per ton (or 1.25-2.5%) of feed. This level of application reduces fines from 25 to 60% in comparison with pellets containing no binder.
Lignosulfonates contain no protein and little metabolizable energy and are therefore unpopular in nutritionally dense formulations, e.g., poultry feeds and pig starter feeds, due to the diluting effect they have on the feed. In addition, lignosulfonates are thought to be unpalatable to piglets and young pigs, limiting their use in pig starter feeds. Manufactures of poultry and pig starter feeds would therefore benefit from a binder which performs as well as a standard lignosulfonate but applied at a lower inclusion rate, namely, at 5-10 pounds per ton of feed. Such a binder would reduce the diluting effect of the binder, and correspondingly increase the available nutrition to be supplied to the animal.
Several "low inclusion" binders have been introduced to the feed industry. These include Nutraflex, a protein colloid manufactured by Swift Company, Hercule's Cellulose Gum, a carboxymethyl cellulose, Production Aid ES, a lignosulfonate-starch blend produced by Cravac Industries, and Basfin, a ureaformaldehyde resin marketed by BASF. Each of these products provides some improvement in pellet quality, but none can produce fines reduction equal to that which occurs when lignosulfonate binders are used at their recommended dosages.
In addition to the above noted "low inclusion" binders, there are attempts in the prior art to improve the binding property of lignosulfonate as an animal feed binder. Thus, Canadian Patent No. 1,203,414 (Apr. 23, 1986) reveals a feed composition comprising a feedstuff and a lignosulfonate-based pelleting aid, characterized in that the pelleting aid comprises a dried, substantially water soluble, sulfonated lignin containing material, which has been modified by crosslinking such as with formaldehyde to increase its molecular weight and thus its solution viscosity. In U.S. Pat. No. 4,871,825 (Oct. 3, 1989), there is disclosed a binder composed of a graft copolymer of high molecular weight sulfonated lignin material and an acrylic compound, said binder exhibiting at least twice as good binding power as a commercial "low inclusion" binder, Production Aid ES. Recently, in U.S. Pat. No. 4,952,415 (Aug. 28, 1990) there is revealed an animal feed composition and method of compounding animal feed utilizing as a binder a copolymer of a sulfonated lignin material and a monomer such as acrylic acid, maleic acid, and methacrylic acid. These and other prior art binders, although showing improved binding property, have not proven to have as great effectiveness as is desirable. The introduction of foreign matters to lignosulfonate in making the copolymer binder raises a concern about its suitability to be used in the animal feed. It thus becomes desirable to have a "low inclusion" binder that is totally based on lignosulfonate, and contains no added chemical entities. It is also beneficial to have an effective binder that can be produced by a simple and low cost method.
A major object of this invention is to provide an effective animal feed binder.
Another object of this invention is to provide a binder from lignosulfonate.
An additional object of this invention is to provide a simple process for the production of the animal feed binder.
A further object of this invention is to provide a feed binder that is produced without addition of foreign chemicals to lignosulfonate.
Other objectives, features and advantages of this invention will be evident from the following detailed description.